Process of making elbows.



v C. A. DIES.

PROCESS OF MAKING ELBOWS.

APPLICATION FILED FEB. I5. 1912. RENEWED sumac. 191a.

m I U w p. M M n N J d m w 7 m H r A m m h Wu C. A. DIES.

PROCESS OF MAKING ELBOWS.

APPLluATlON man FEB. 15. 1912. RENEWED SEPT.30. 1916.

1,225,788, Patented 15,1917.

3 SHE HEET 2.

C. A. DIES.

PROCESS OF MAKING ELBOWS.

APPLICATION FILED FEB-15, 1912- RENEWED SEPT. 30, l9l6- 1,225,788 Paten ted May15,1917.

3 SHEETS-SHEET 3- manna canton.

CHARLES A. DIES, OF CHICAGO, ILLINOIS, ASSIGN'OR 'IO CLAYTON MARK, OF CHICAGO,

ILLINOIS.

PROCESS OF MAKING ELBOWS.

Specification of Letters Patent.

Application filed February 15, 1912, Serial No. 677,790. Renewed September 30, 1916. Serial No. 123,015.

To all whom it may concern:

Be it known that I, CHARLES A. DIES, a citizen of the United States, and residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in the Process of Making Elbows, of which the following is a complete specification.

The main objects of this invention are to provide an improved process for making elbows adapted to greatly cheapen the product; to provide an improved process of making elbows from tubular stock; to provide an improved process of making elbows Wherebyelbows of great strength may be formed from comparatively light stock; to-

provide a process of making elbows by means of dies to form the stock but without the use of any internal means to hold the stock in place; and to provide a. process of making elbows'by means of which a perfectly formed, strong and durable product may be turned out with great rapidity.

A specific embodiment of the invention is illustrated in the accompanying drawings, in which:

Figure 1 is a longitudinal section of the reducing punch and die with a blank therein ready to be operated upon.

Fig. 2 is a longitudinal section of the blank after the reducing operation.

Fig. 3 is a section taken on line 33 of Fig. 2. p I

Fig. 4 is a perspective view of the bending punch.

Fig. 5 is a perspective view of the bending die.

Fig. 6 is a longitudinal central section of the bending punch taken between the pilot jaws.

Fig. 7 is a the bending punch taken through the p11ot aws.

1 Fig. 8 is a longitudinal section of the bending die.

Fig. 9 is a transverse section of the bending die.

Fig. 10 is a longitudinal section of the blank after being operated upon by the bending punchand die.

Fig. 11 is a transverse section of the blank shown in Fig. 10. h

Fig. 12 is a plan view of the sizing punch.

Fig. 13 is a side elevation of the slzmg punch.

longitudinal central section of d Fig. 14 isa side elevation of the sizing Fig. 15 is a plan view of the sizing die.

Fig. 16 is a side elevation of the blank formed on the side of the blank diametrically opposite from the uncompressed portion 3 and gradually decreasing in each direction toward said uncompressed portion 3.

In order to accom lish the above mentioned reductions of t e ends of the blank,

a punch 4 and a die 5 are'provided, each of which has a bore or seat 6 therein of a size and shape at its outer end to receive the unreduced end of the blank 1. Each seat 6 is restricted more or less abruptly for a portion of its length from its outer end inwardly on all sides but one thereof, the side or, portion of the seat having the greatest amount of restriction being diametrically opposite from the unrestricted side. The inner end of the seat is thereforeof less diameter than the outer portion thereof and is axially ofi center -with respect thereto.

When the punch is moved toward the die it forces the ends of the blank into said seats and the restricted portions of the seats compress the stock in the contiguous sides or parts of the-blank, with the result that the compressed portions 7 of the blank as well as the intermediate unreduced portions 8 thereof are slightly thickened and contain more stock than do the unreduced portions of the ends due to the movement or displacement of the metal under the action of the reducing punch and die.

When the punch 4 is retracted from. the die 5 the ejectors 9 eject the blank therefrom in the usual manner.

The next operation in the process is to bend the blank 1 to the desired angle for the elbow. The elbow herein shown is a 90 deg'ree elbow, though elbows of other angles 40 I 1 shown more clearly in Fig. 10. 1

1 The bending: punch is provided on its;

may be: constructed equally well by the process.

' For the purpose of bending the blank to the sides of the die at the inner ends or backs of the grooves 13 are thesteel protecting or expansion plates 14 which are held in place by the rivets 15 passing through the body of the die; The plates 14: set into the sides or" the seat '12 and the upper edges of said plates are'shaped to conform to the parts of the seat which they displace. The plates 11 are rmitted a very slight outward movement on the rivets so as to yield slightly when the blank is being bent and thereby Y prevent the edges of the seat 12 breaking should there be slight variations in the size of the blank and also to permit the blank tov assume the pro er cross-sectional curvature. The seat 12 is also of slightly greater width at its center than at its ends,

as shown more clearly in Fig. 9, so as to permit the stock of the blank 1 to move toward the center and expand. the blank laterally at its central portion during the bending operation, andthereby insure the complete filling of the dies in the last or sizing 1 operation. Such lateral expansion is due to the fact that in-b'endin the blank the cent'ral'portion 8 tends to atten' longitudinally of the blank, or rather bend on a longer radius than that of the finished elbow, as

under side with atransversely concaved seat 17 which is shaped longitudinally to conform to\ the inner or shorter angle of the elbow. On each side of the seat 17 is a downwardly directed pilot jaw 18, adapted,v

as the punch descends, to enter the pilot grooves 13 and back up or support the expansion plates 14, and also support the sides of the blank against too great lateral clearly if thereduced portions of its ends downwardly expansion. The seat 17 is also of slightly greater width at its centralportion t-h' its ends to conform to the seat 12 die 11, and its depth is slightly less than that of the seat 12, so that it will causegfthe blank to assume a slightly elliptical shape in cross section. After the bending operation theblank is slightly moreelliptical at its cent than atfits ends, as shown more 1g. 11. blank 1 The is placed in the die 11 with or 1 ing in the seat 1'2,"and when the punch 10 1s broughtonto the blank itforms the blank to the shape shown in Figs. 10 and "11. The punch 10 and die 11 are provided with ejectors 19 adapted to eject the blank therefrom after the bending operation.

After the bending operation has been completed the blanks are ready for the sizing or truing operation to bring them to the proper uniform size throughout. For the purpose of sizing the blank the sizing punch 20 and the sizing die 21 are provided with seats 22 and 23, respectively, in their contiguous faces, which seats are semi-circular in cross section and of uniform size throughout their lengths, and are formed in the exact angle desired for the completed elbow.

-The punch 20 and the die 21 are each provided with a guide pin 24in register with and adapted to enter an aperture 25 in the other, to hold the punch and die in unvaryin relation to each other when in, operation. he operation of the process shown and described is-as follows: When the blank 1 is placed in the reducing die 5 and the re- Iducing punch is brought down onto it, one

end of the blank is forced into the seat 6 of the die'and the other end of the blank is forced into the seat 6 in the punch, thereby forming the reduced or restricted ends 2 which are axially offset in the same direction from the longitudinal axes of the blank.

The reducing operation thickens the stock on the sides of the blank where the reduction takes place, as well as in the intermediate portion 8, so asto compensate for a slight drawing of the metal along the long side of the elbow during the bending operation, and thereby render the walls of the finished elbow of uniform thickness throughout.

After the'reduc'ing operation the blank is laid in the' bending die 11 with the portion 8 thereof downwardly, and when thepunch 10 is brought into contact with the blank, the latter is bent centrally to the desired angle. Since the seats12 and 17 are slightly larger at their centers than at their ends, the blank is permitted to. expand laterally and contract vertically at its central portion, as

shown in Figs. 10 and 11, so as to insure the complete filling of the dies in the sizing operation.

After the bending operation-the blank is pffiij'd in the sizing die and when the sizing punch is brought against the same the blank isbrought to a uniform size throughout its When the blank is placed in the sizing "die the long side 8 of the blank is out of contactwitlf' the long side of the angle of the seat 23, as shown more clearlyl' in Fig. 15,. and the remaining portion of the blank fits loosely in the seat. When the punch 20 is brought against the blank, the latter is brought back to cylindrical form and the stock flows toward the sides completely fillerations on the blank is ing the dies and making the elbow of uniform size.

The ends of the blank may be trimmed oil in any desired manner, and headed and threaded. 1

Itwill be noticed that in none ofthe opany internal supporting means required to support the stock. In the bending operation the elongation of the long side of the angle and the tendency to form an elliptical cross sectional shape prevent collapse of the stock.

While but one specificembodiment of the inventionhas been herein shown and described it will be understood that many details of the process described may be Varied or omitted without departing from the scope of the claims.

I claim:

1. The process of making elbows, comprising reducing the ends of a tubular blank and thickening the walls of that side of the blank designed to form the long side of the elbow, then bending the blank centrally to the desired angle. I T

2. The process of making elbows, comprising thickening by compression (in varying degrees from ends toward the center) the stock along one side of a tubular blank, then bending the blank toward the opposite side to the desired angle.

3. The process of making elbows, comprising reducing the ends of a tubular blank,

. bending the blank to the desired angle and forming it to an elliptical cross sectional shape, then truing the blank to a uniform diameter.

. 4. The process of making elbows, comprising bending an internally unsupported tubular blank to the desired angle, and re ducing it to an elliptical cross sectional shape, then sizing the blank to bring it to a uniform diameter.

5. The process of maln'ng elbows, comprising reducing the diameter of the ends of a tubular blank and thickening the walls of one side of the blank, bending the blank to the desired angle with the thickened walls forming the long side of the angle and shaping the blank to an elliptical form, then truing the blank to a uniform diameter.

6. The process of making elbows, comprising bending a tubular-blank to the desired angle and forming it to an elliptical cross sectional shape with greater ellipticity at its center than at its ends, then shaping the blank to a uniform diameter.

7 The process of making elbows, compris ing reducing the ends of a tubular blank from one'side of the blank, bending the internally unsupported blank to the desired angle in a direction opposite from the reduced portion and expanding the blank laterally, then shaping the blank to a uniform diameter throughout.

CHARLES ALBERT Witnesses:

I ESTHER DAUGHERTY,

CLARENCE MARK.

DIES. 

